Fix T58609 Subdivision Surface modifier, "Optimal Display" not working

I tried to make it progressive using the wireframe slide but it did not
work well.

So taking the most straight forward way.

diff --git a/source/blender/draw/intern/draw_cache_impl_mesh.c b/source/blender/draw/intern/draw_cache_impl_mesh.c
index 5d7e588b9048e267fe4f44f5197f4e758b664d92..5e0826e9bed9aecb25c2c7addcec654281ed461e 100644 (file)
--- a/source/blender/draw/intern/draw_cache_impl_mesh.c
+++ b/source/blender/draw/intern/draw_cache_impl_mesh.c
@@ -4328,7 +4328,6 @@ static GPUVertBuf *mesh_batch_cache_create_edges_overlay_texture_buf(
 
        for (int i = 0; i < tri_len; i++) {
                uint vdata[3] = {0, 0, 0};
-               bool edge_is_real[3];
                bool face_has_edges = false;
 
                const MVert *mvert = rdata->mvert;
@@ -4340,15 +4339,20 @@ static GPUVertBuf *mesh_batch_cache_create_edges_overlay_texture_buf(
                for (j = 2, j_next = 0; j_next < 3; j = j_next++) {
                        const MEdge *ed = &medge[mloop[mlt->tri[j]].e];
                        const uint tri_edge[2]  = {mloop[mlt->tri[j]].v, mloop[mlt->tri[j_next]].v};
-                       edge_is_real[j] = (
-                               ((ed->v1 == tri_edge[0]) && (ed->v2 == tri_edge[1])) ||
-                               ((ed->v1 == tri_edge[1]) && (ed->v2 == tri_edge[0])));
+
+                       if ((((ed->v1 == tri_edge[0]) && (ed->v2 == tri_edge[1])) ||
+                            ((ed->v1 == tri_edge[1]) && (ed->v2 == tri_edge[0]))) &&
+                            (ed->flag & ME_EDGERENDER) != 0)
+                       {
+                               /* Real edge. */
+                               vdata[j] |= (1 << 30);
+                       }
                }
 
-               if (edge_is_real[0] || edge_is_real[1] || edge_is_real[2]) {
+               /* If at least one edge is real. */
+               if (vdata[0] || vdata[1] || vdata[2]) {
                        /* Decide if face has at least a "dominant" edge. */
 
-                       /* Try to do the same facing approximation as in the shader. */
                        float fnor[3];
                        if (reduce_len) {
                                normal_tri_v3(fnor,
@@ -4360,19 +4364,21 @@ static GPUVertBuf *mesh_batch_cache_create_edges_overlay_texture_buf(
                        for (int e = 0; e < 3; e++) {
                                int v0 = mloop[mlt->tri[e]].v;
                                int v1 = mloop[mlt->tri[(e + 1) % 3]].v;
-                               vdata[e] = (uint)v0;
-                               EdgeAdjacentVerts *eav = BLI_edgehash_lookup(eh, v0, v1);
-                               /* Real edge */
-                               if (edge_is_real[e]) {
-                                       vdata[e] |= (1 << 30);
+                               /* The only breakage it would cause is drawing issues. */
+                               /* BLI_assert(3FFFFFFF > v0); */
+                               vdata[e] |= (uint)v0;
+                               /* Non-real edge. */
+                               if (vdata[e] == 0) {
+                                       continue;
                                }
+                               EdgeAdjacentVerts *eav = BLI_edgehash_lookup(eh, v0, v1);
                                /* If Non Manifold. */
                                if (eav->vert_index[1] == -1) {
                                        face_has_edges = true;
                                        vdata[e] |= (1u << 31);
                                }
                                /* Search for dominant edge. */
-                               if (reduce_len && !face_has_edges && edge_is_real[e]) {
+                               if (reduce_len && !face_has_edges) {
                                        int v2 = mloop[mlt->tri[(e + 2) % 3]].v;
                                        /* Select the right opposite vertex */
                                        v2 = (eav->vert_index[1] == v2) ? eav->vert_index[0] : eav->vert_index[1];